feat(app): add error/loading boundaries across all dashboard routes and new routes

- Add error.tsx and loading.tsx boundaries for admin, parent, student, teacher routes

- Add admin announcements edit, audit-logs overview, curriculum-map, invitation-codes, permissions, questions, roles routes

- Add admin elective detail and components, files, course-plans, users, scheduling boundaries

- Add messages group-compose route

- Add parent course-plans, elective, grades report-card, practice routes

- Add student course-plans, elective detail, error-book dialogs, grades report-card, learning study-path, leave, schedule boundaries

- Add teacher attendance report, classes boundaries, course-plans boundaries, elective, exams analytics/edit-rich/all/create/new, grades report-card, homework boundaries, leave, lesson-plans calendar

- Add auth loading, onboarding loading, api cron

src/app/(dashboard)/teacher/classes/my/[id]/page.tsx

@@ -1,10 +1,13 @@
+import type { Metadata } from "next"
 import type { JSX } from "react"
 import { notFound } from "next/navigation"
+import { getTranslations } from "next-intl/server"
 
 import { requirePermission } from "@/shared/lib/auth-guard"
 import { Permissions } from "@/shared/types/permissions"
 import { getClassHomeworkInsights, getClassSchedule, getClassStudentSubjectScoresV2, getClassStudents } from "@/modules/classes/data-access"
 import { ClassAssignmentsWidget } from "@/modules/classes/components/class-detail/class-assignments-widget"
+import { ClassErrorBoundary } from "@/modules/classes/components/class-error-boundary"
 import { ClassTrendsWidget } from "@/modules/classes/components/class-detail/class-trends-widget"
 import { ClassHeader } from "@/modules/classes/components/class-detail/class-header"
 import { ClassOverviewStats } from "@/modules/classes/components/class-detail/class-overview-stats"
@@ -13,6 +16,14 @@ import { ClassStudentsWidget } from "@/modules/classes/components/class-detail/c
 
 export const dynamic = "force-dynamic"
 
+export async function generateMetadata(): Promise<Metadata> {
+  const t = await getTranslations("classes")
+  return {
+    title: `${t("metadata.classDetail")} - Next_Edu`,
+    description: t("metadata.classDetail"),
+  }
+}
+
 export default async function ClassDetailPage({
   params,
 }: {
@@ -66,45 +77,47 @@ export default async function ClassDetailPage({
 
   return (
     <div className="flex min-h-screen flex-col bg-muted/10">
-      <ClassHeader
-        classId={insights.class.id}
-        name={insights.class.name}
-        grade={insights.class.grade}
-        homeroom={insights.class.homeroom}
-        room={insights.class.room}
-        schoolName={insights.class.schoolName}
-        studentCount={insights.studentCounts.total}
-      />
-
-      <div className="flex-1 space-y-6 p-6">
-        {/* Key Metrics */}
-        <ClassOverviewStats
-          averageScore={insights.overallScores.avg}
-          submissionRate={totalSubmissionRate * 100}
-          papersToGrade={papersToGrade}
-          overdueCount={overdueCount}
+      <ClassErrorBoundary>
+        <ClassHeader
+          classId={insights.class.id}
+          name={insights.class.name}
+          grade={insights.class.grade}
+          homeroom={insights.class.homeroom}
+          room={insights.class.room}
+          schoolName={insights.class.schoolName}
+          studentCount={insights.studentCounts.total}
         />
 
-        <div className="grid grid-cols-1 gap-6 lg:grid-cols-3">
-          {/* Main Content Area (Left 2/3) */}
-          <div className="min-w-0 space-y-6 lg:col-span-2">
-            <ClassTrendsWidget assignments={assignmentSummaries} />
-            <ClassStudentsWidget
-              classId={insights.class.id}
-              students={studentSummaries}
-            />
-          </div>
+        <div className="flex-1 space-y-6 p-6">
+          {/* Key Metrics */}
+          <ClassOverviewStats
+            averageScore={insights.overallScores.avg}
+            submissionRate={totalSubmissionRate * 100}
+            papersToGrade={papersToGrade}
+            overdueCount={overdueCount}
+          />
 
-          {/* Sidebar Area (Right 1/3) */}
-          <div className="min-w-0 space-y-6">
-            <ClassScheduleWidget classId={insights.class.id} schedule={schedule} />
-            <ClassAssignmentsWidget
-              classId={insights.class.id}
-              assignments={assignmentSummaries}
-            />
+          <div className="grid grid-cols-1 gap-6 lg:grid-cols-3">
+            {/* Main Content Area (Left 2/3) */}
+            <div className="min-w-0 space-y-6 lg:col-span-2">
+              <ClassTrendsWidget assignments={assignmentSummaries} />
+              <ClassStudentsWidget
+                classId={insights.class.id}
+                students={studentSummaries}
+              />
+            </div>
+
+            {/* Sidebar Area (Right 1/3) */}
+            <div className="min-w-0 space-y-6">
+              <ClassScheduleWidget classId={insights.class.id} schedule={schedule} />
+              <ClassAssignmentsWidget
+                classId={insights.class.id}
+                assignments={assignmentSummaries}
+              />
+            </div>
           </div>
         </div>
-      </div>
+      </ClassErrorBoundary>
     </div>
   )
 }